398464909 has 2 divisors, whose sum is σ = 398464910. Its totient is φ = 398464908.

The previous prime is 398464883. The next prime is 398464933. The reversal of 398464909 is 909464893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 226592809 + 171872100 = 15053^2 + 13110^2 .

It is an emirp because it is prime and its reverse (909464893) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 398464909 - 2²¹ = 396367757 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398464109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199232454 + 199232455.

It is an arithmetic number, because the mean of its divisors is an integer number (199232455).

Almost surely, 2^398464909 is an apocalyptic number.

It is an amenable number.

398464909 is a deficient number, since it is larger than the sum of its proper divisors (1).

398464909 is an equidigital number, since it uses as much as digits as its factorization.

398464909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1679616, while the sum is 52.

The square root of 398464909 is about 19961.5858337959. The cubic root of 398464909 is about 735.8625374628.

The spelling of 398464909 in words is "three hundred ninety-eight million, four hundred sixty-four thousand, nine hundred nine".